Israel frank miller



(No Modgl.)

I. P. MILLER.

AUTOMATIC SELF CLOSING DOOR.

Patented Mar. 3, 1896.

UNITED STATES PATENT OFFICE.

ISRAEL FRANK MILLER, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO LEUTELLER H.TOURTELLOTTE, OF SAME PLACE.

AUTOMATIC SELF-CLOSING DOOR.

SPECIFICATION forming part of Letters Patent No. 555,652, dated March 3,1896. Application filed December 12,1895. Serial No. 571,890. (Nomodel.)

To all whom it may concern.-

Be it known that I, ISRAEL FRANK MILLER, of Boston, county ofSuffolk,and State of Massachusetts, have invented an Improvement inAutomatic Self-Closing Doors, of which the following description, inconnection with the accompanying drawings, is a specification, likeletters on the drawings representing like parts.

This invention has for its object to improve the construction ofautomatic self closing doors especially designed for mills and otherbuildings.

Prior to this invention an automatic selfclosing door has been madewhich consisted of a door arranged to slide on a declining track toclose automatically, and as a means for holding it open a cord wasconnected to the door which passed over a pulley and thence to a fusiblelink, and another cord was connected at one end to said fusible link andhad attached to its opposite end a weight of a size substantially tobalance the door. Thus the weight held the door open, but in case thefusible link melted, the weight became detached or disconnected from thedoor just as if the cord had broken, thereby permitting the door toclose automatically. In case the fusible link melts, the door isexpected to start and close by gravity, but it oftentimes sticks anddoes not start at all, although if once started its action is quitecertain. The door is usually opened wide, and the weight at such timerests upon the floor; but if it is desired to open the door part waycareful adjustment of the weight is necessary in order that the door mayremain in such position, as the friction to be overcome varies.

In accordance with this invention the door is arranged and adapted toslide on a declining track to close automatically, and to hold the dooropen a cord is provided which is quite independent of the door and whichis connected at one end with a pivoted weight, so arranged as to turn onits pivot when released and in falling to strike the door a severe blowand thereby materially assist in starting it. The other end of the cordis at tached to the fusible link, and another cord is provided, one endof which is attached to said fusible link, and in case of a single doorits other end is attached to a fixed point; but

in case of a double door this latter cord instead of being attached to afixed point will be attached to another pivoted weight located adjacentto the other door, and when the link melts both weights will fall andstrike the doors. The double doors are arranged to slide on tracks whichdecline toward each other, and each door will have a sheave-plate'thatis, a plate carrying two or more sheaves over and under which the cordpasses-such a device frictionally connecting the door with the cord,permitting the door to be moved along the cord in either directionfreely, yet to remain in whatever position it may be left.

Figure 1 shows in front elevation a double door provided with automaticself-closing devices embodying this invention; Fig.2,a modificationshowing my improved devices applied to a single door; Fig. 3, a detailof the pivoted weight, and Fig. 4 a detail of the bracket to which theweight is pivoted.

The doors co 1) are arranged and adapted to slide upon tracks a b whichdecline toward each other, the hangers and tracks being of any desirableconstruction. A cord 0 is provided, which, as shown in Fig. 1, is madequite long and has at the middle a fusible link cl, which is so arrangedas to occupy a position about midway the arch. The ends of the cord 0are attached to pivoted weights e. These weights are made as bell-cranklevers, pivoted at e, each having a block e upon one of its arms, whileits other arm is connected with the cord. A bracket f is secured to thewall and is adapted to serve as a pivotal support for the weight.

A sheave-plate g is secured to each sliding door, bearing two or moresheaves g, over and under which the cord 0 passes, as represented inFig. 1. This sheave-plate connected with the cord, as shown, serves toconnect the door frictionally with the cord, permitting it to be movedalong freely, yet be held at whatever point it may be placed. Thegrooves in the sheaves g are made quite shallow, so that in case thefusible link melts and the cord drops it will readily slip off or out ofengagement with the sheaves.

When the fusible link melts, the pivoted weights will be released andturning on their pivots will strike the doors a severe blow, assistingin starting them along the tracks.

The blocks e have upon their rear sides projections 0 which engage theedges of the doors when the weights are released.

It will be seen that the doors are not directly connected with thecords, so that when they close by their automatic action they do not inany way draw the cord along; also, that the doors may be easily movedalong the cord and remain in any position in which. they may be placed,and that when the weights are automatically released they assist instarting the doors along the tracks.

As contrasted with prior constructions, the weights do not act tobalance the door, but to give suitable tension to the cord, so that thefriction 011 the sheaves y will be sullicient to hold the door inwhatever position it maybe placed.

In case of a single door one end of the cord will be attached to a fixedpoint, as represented at h, Fig. I

I claim- 1. A door adapted to slide upon a declining track to closeautomatically, combined with a cord having a fusible link, supports foreach end thereof, and a friction device for connecting the door withsaid cord, permitting it to slide along the cord and to remain inwhatever position thereon it may be set, substantially as described.

2. A door adapted to slide upon a declining track to closeautomatically, combined with a cord 0 having a fusible link (7, and afriction device, such as a sheave-plate secured to the door and havingtwo or more sheaves, over and under which the cord passes, substantiallyas described.

A door adapted to slide upon a declining track to close automatically,combined with a cord 0 having afusible link (1, a weight for holding thecord taut, and a friction device, such as a sheave-plate, secured to thedoor, and having two or more sheaves over and under which the cordpasses, substantially as described.

at. A door adapted to slide upon a declining track to closeautomatically, con'ibined with a cord 0 having a fusible link cl, meansfor connecting the door with said cord, and a pivoted weight to whichone end of said cord is attached, adapted when released to fall. andstrike the door, substantially as described.

5. Two doors adapted to slide upon tracks which decline toward eachother, combined with a cord 0 having a fusible link (I, pivoted weightsattached to the ends of said cord, and afriction device, such as asheave-plate having two or more sheaves, for connecting each door withthe cord, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ISRAEL FRANK MILLER.

\Vi tnesses:

13. J. Novas, 11. ll. DAVIS.

